Semiconductor device and method

ABSTRACT

In accordance with some embodiments a via is formed over a semiconductor device, wherein the semiconductor device is encapsulated within an encapsulant  129 . A metallization layer and a second via are formed over and in electrical connection with the first via, and the metallization layer and the second via are formed using the same seed layer. Embodiments include fully landed vias, partially landed vias in contact with the seed layer, and partially landed vias not in contact with the seed layer.

PRIORITY CLAIM AND CROSS-REFERENCE

This application is a divisional to U.S. patent application Ser. No.16/028,874, filed on Jul. 6, 2018, entitled “Semiconductor Device andMethod,” which claims priority to and the benefit of U.S. ProvisionalApplication No. 62/564,134, filed on Sep. 27, 2017, entitled“Semiconductor Device and Method,” which applications are herebyincorporated herein by reference in its entirety.

BACKGROUND

The semiconductor industry has experienced rapid growth due tocontinuous improvements in the integration density of a variety ofelectronic components (e.g., transistors, diodes, resistors, capacitors,etc.). For the most part, this improvement in integration density hascome from repeated reductions in minimum feature size (e.g., shrinkingthe semiconductor process node towards the sub-20 nm node), which allowsmore components to be integrated into a given area. As the demand forminiaturization, higher speed and greater bandwidth, as well as lowerpower consumption and latency has grown recently, there has grown a needfor smaller and more creative packaging techniques of semiconductordies.

As semiconductor technologies further advance, stacked and bondedsemiconductor devices have emerged as an effective alternative tofurther reduce the physical size of a semiconductor device. In a stackedsemiconductor device, active circuits such as logic, memory, processorcircuits and the like are fabricated at least partially on separatesubstrates and then physically and electrically bonded together in orderto form a functional device. Such bonding processes utilizesophisticated techniques, and improvements are desired.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that, in accordance with the standard practice in the industry,various features are not drawn to scale. In fact, the dimensions of thevarious features may be arbitrarily increased or reduced for clarity ofdiscussion.

FIGS. 1A-6 illustrate fully landed vias on metallization layers, inaccordance with some embodiments.

FIGS. 7A-11 illustrate partially landed vias in contact with a seedlayer, in accordance with some embodiments.

FIGS. 12A-16 illustrate partially landed vias not in physical contactwith a seed layer, in accordance with some embodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the invention. Specificexamples of components and arrangements are described below to simplifythe present disclosure. These are, of course, merely examples and arenot intended to be limiting. For example, the formation of a firstfeature over or on a second feature in the description that follows mayinclude embodiments in which the first and second features are formed indirect contact, and may also include embodiments in which additionalfeatures may be formed between the first and second features, such thatthe first and second features may not be in direct contact. In addition,the present disclosure may repeat reference numerals and/or letters inthe various examples. This repetition is for the purpose of simplicityand clarity and does not in itself dictate a relationship between thevarious embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

Embodiments will now be described with respect to an ultra high densityredistribution layer interconnect of an integrated fan out (InFO)package. However, embodiments are not intended to be limited to theembodiments described herein but, rather, could be used in a widevariety of applications.

With reference now to FIG. 1A, there is shown a first carrier substrate101, a polymer layer 103, a first semiconductor device 105 and a secondsemiconductor device 107 over the first carrier substrate 101. The firstcarrier substrate 101 comprises, for example, silicon based materials,such as glass or silicon oxide, or other materials, such as aluminumoxide, combinations of any of these materials, or the like. The firstcarrier substrate 101 is planar in order to accommodate an attachment ofthe first semiconductor device 105 and the second semiconductor device107.

The polymer layer 103 is placed over the first carrier substrate 101 andis utilized in order to provide protection to, e.g., the firstsemiconductor device 105 and the second semiconductor device 107 oncethe first semiconductor device 105 and the second semiconductor device107 have been attached. In an embodiment the polymer layer 103 is adielectric such as an epoxy-based thermal-release material, which losesits adhesive property when heated, such as a light-to-heat-conversion(LTHC) release coating. In other embodiments, the polymer layer 103 maybe an ultra-violet (UV) glue, which loses its adhesive property whenexposed to UV lights. The polymer layer 103 may be dispensed as a liquidand cured, may be a laminate film laminated onto the first carriersubstrate 101, or the like.

In an embodiment the first semiconductor device 105 may be a first dieand comprise a first substrate 109, first active devices, first diemetallization layers, first contact pads 111, a first passivation layer113, and first external connectors 115. The first substrate 109 maycomprise silicon, doped or undoped, or an active layer of asemiconductor-on-insulator (SOI) substrate. The first substrate 109 mayinclude other semiconductor material, such as germanium; a compoundsemiconductor including silicon carbide, gallium arsenic, galliumphosphide, indium phosphide, indium arsenide, and/or indium antimonide;an alloy semiconductor including SiGe, GaAsP, AlInAs, AlGaAs, GaInAs,GaInP, and/or GaInAsP; or combinations thereof. Other substrates, suchas multi-layered or gradient substrates, may also be used.

The first active devices comprise a wide variety of active devices andpassive devices such as transistors, diodes, capacitors, resistors,inductors and the like that may be used to generate the desiredstructural and functional requirements of the design for the firstsemiconductor device 105. The first active devices may be formed usingany suitable methods either within or else on the first substrate 109.

The first die metallization layers are formed over the first substrate109 and the first active devices and are designed to connect the variousactive devices to form functional circuitry. In an embodiment the firstdie metallization layers are formed of alternating layers of dielectricand conductive material and may be formed through any suitable process(such as deposition, damascene, dual damascene, etc.). In an embodimentthere may be layers of metallization separated from the first substrate109 by at least one interlayer dielectric layer (ILD), but the precisenumber of first die metallization layers is dependent upon the design ofthe first semiconductor device 105.

The first contact pads 111 may be formed over and in electrical contactwith the first die metallization layers. The first contact pads 111 maycomprise aluminum, but other materials, such as copper, mayalternatively be used. The first contact pads 111 may be formed using adeposition process, such as sputtering, to form a layer of material andportions of the layer of material may then be removed through a suitableprocess (such as photolithographic masking and etching) to form thefirst contact pads 111. However, any other suitable process may beutilized to form the first contact pads 111. The first contact pads 111may be formed to have a thickness of greater than about between about0.1 μm and about 10 μm, such as about 1.45 μm.

The first passivation layer 113 may be formed on the first substrate 109over the first die metallization layers and the first contact pads 111.The first passivation layer 113 may be made of one or more suitabledielectric materials such as polybenzoxazole (PBO), although anysuitable material, such as polyimide or a polyimide derivative, mayalternatively be utilized. The first passivation layer 113 may be formedusing, e.g., a spin-coating process to a thickness of between about 5 μmand about 25 μm, such as about 7 μm, although any suitable method andthickness may alternatively be used.

The first external connectors 115 may be formed to provide conductiveregions for contact between the first contact pads 111 and, e.g., firstvias 135. In an embodiment the first external connectors 115 may beconductive pillars and may be formed by initially forming a photoresistover the first passivation layer 113 to a thickness between about 5 μmto about 20 μm, such as about 10 μm. The photoresist may be patterned toexpose portions of the first passivation layers 113 through which theconductive pillars will extend. Once patterned, the photoresist may thenbe used as a mask to remove the desired portions of the firstpassivation layer 113, thereby exposing those portions of the underlyingfirst contact pads 111 to which the first external connectors 115 willmake contact.

The first external connectors 115 may be formed within the openings ofboth the first passivation layer 113 and the photoresist. The firstexternal connectors 115 may be formed from a conductive material such ascopper, although other conductive materials such as nickel, gold, ormetal alloy, combinations of these, or the like may also be used.Additionally, the first external connectors 115 may be formed using aprocess such as electroplating, by which an electric current is runthrough conductive portions of the first contact pads 111 to which thefirst external connectors 115 are desired to be formed, and the firstcontact pads 111 are immersed in a solution. The solution and theelectric current deposit, e.g., copper, within the openings in order tofill and/or overfill the openings of the photoresist and the firstpassivation layer 113, thereby forming the first external connectors115. Excess conductive material and photoresist outside of the openingsof the first passivation layer 113 may then be removed using, forexample, an ashing process, a chemical mechanical polish (CMP) process,combinations of these, or the like.

However, as one of ordinary skill in the art will recognize, the abovedescribed process to form the first external connectors 115 is merelyone such description, and is not meant to limit the embodiments to thisexact process. Rather, the described process is intended to be merelyillustrative, as any suitable process for forming the first externalconnectors 115 (such as placing a seed layer 139 or anundermetallization layer before the rest of the first externalconnectors 115) may alternatively be utilized. All suitable processesare fully intended to be included within the scope of the presentembodiments.

Optionally, a protection layer 117 may be formed over the first externalconnectors 115 after formation. In an embodiment the protection layer117 may be formed to cover the exposed top and side surfaces of thefirst external connectors 115 during further processing, and may be madeof, e.g., a low temperature cured polyimide (LTPI) or high temperaturecured PBO (HTPBO). However, any suitable material may be utilized.

A die attach film (DAF) 119 may be placed on an opposite side of thefirst substrate 109 in order to assist in the attachment of the firstsemiconductor device 105 to the polymer layer 103. In an embodiment thedie attach film 119 is any suitable adhesive, epoxy resin, a phenolresin, acrylic rubber, silica filler, or a combination thereof, and isapplied using a lamination technique. However, any other suitablealternative material and method of formation may alternatively beutilized.

FIG. 1A additionally illustrates a placement of the first semiconductordevice 105 onto the polymer layer 103 along with a placement of thesecond semiconductor device 107. In an embodiment the secondsemiconductor device 107 may comprise a second substrate 121, secondactive devices, second die metallization layers, second contact pads123, a second passivation layer 125, and second external connectors 127.In an embodiment the second substrate 121, the second active devices,the second die metallization layers, the second contact pads 123, thesecond passivation layer 125, and the second external connectors 127 maybe similar to the first substrate 109, the first active devices, thefirst die metallization layers, the first contact pads 111, the firstpassivation layer 113, and the first external connectors 115, althoughthey may also be different.

In an embodiment the first semiconductor device 105 and the secondsemiconductor device 107 may be placed onto the polymer layer 103 using,e.g., a pick and place process. However, any other method of placing thefirst semiconductor device 105 and the second semiconductor device 107may also be utilized.

FIG. 1A also illustrates an encapsulation of the first semiconductordevice 105 and the second semiconductor device 107. The encapsulationmay be performed in a molding device, which may comprise a top moldingportion and a bottom molding portion separable from the top moldingportion. When the top molding portion is lowered to be adjacent to thebottom molding portion, a molding cavity may be formed for the firstcarrier substrate 101, the first semiconductor device 105, and thesecond semiconductor device 107.

During the encapsulation process the top molding portion may be placedadjacent to the bottom molding portion, thereby enclosing the firstcarrier substrate 101, the first semiconductor device 105, and thesecond semiconductor device 107 within the molding cavity. Onceenclosed, the top molding portion and the bottom molding portion mayform an airtight seal in order to control the influx and outflux ofgasses from the molding cavity. Once sealed, an encapsulant 129 may beplaced within the molding cavity.

The encapsulant 129 may be an epoxy or a molding compound resin such aspolyimide, polyphenylene sulfide (PPS), polyetheretherketone (PEEK),poly ether sulphone (PES), a heat resistant crystal resin, combinationsof these, or the like. The encapsulant 129 may be placed within themolding cavity prior to the alignment of the top molding portion and thebottom molding portion, or else may be injected into the molding cavitythrough an injection port, using compression molding, transfer molding,or the like.

Once the encapsulant 129 is placed into the molding cavity such that theencapsulant 129 encapsulates the first carrier substrate 101, the firstsemiconductor device 105, and the second semiconductor device 107, theencapsulant 129 may be cured in order to harden the encapsulant 129 foroptimum protection. While the exact curing process is dependent at leastin part on the particular material chosen for the encapsulant 129, in anembodiment in which molding compound is chosen as the encapsulant 129,the curing could occur through a process such as heating the encapsulant129 to between about 100° C. and about 200° C., such as about 125° C.for about 60 sec to about 3000 sec, such as about 600 sec. Additionally,initiators and/or catalysts may be included within the encapsulant 129to better control the curing process.

However, as one having ordinary skill in the art will recognize, thecuring process described above is merely an exemplary process and is notmeant to limit the current embodiments. Other curing processes, such asirradiation or even allowing the encapsulant 129 to harden at ambienttemperature, may alternatively be used. Any suitable curing process maybe used, and all such processes are fully intended to be included withinthe scope of the embodiments discussed herein.

FIG. 1B illustrates a thinning of the encapsulant 129 in order to exposethe first semiconductor device 105 and the second semiconductor device107 for further processing. The thinning may be performed, e.g., using amechanical grinding, chemical approaches, or chemical mechanicalpolishing (CMP) process whereby chemical etchants and abrasives areutilized to react and grind away the encapsulant 129, the firstsemiconductor device 105 and the second semiconductor device 107 so thatthe first external connectors 115 (on the first semiconductor device105), and the second external connectors 127 (on the secondsemiconductor device 107) have been exposed. As such, the firstsemiconductor device 105 and the second semiconductor device 107 mayhave a planar surface that is also coplanar with the encapsulant 129.

In another embodiment, the grinding may be omitted. For example, if thefirst semiconductor device 105 and the second semiconductor device 107are already exposed after encapsulation, the grinding may be omitted.

Furthermore, while the CMP process described above is presented as oneillustrative embodiment, it is not intended to be limiting to theembodiments. Any other suitable removal process may be used to thin theencapsulant 129, the first semiconductor device 105, and the secondsemiconductor device 107. For example, a series of chemical etches maybe utilized. This process and any other suitable process may be utilizedto planarize the encapsulant 129, the first semiconductor device 105,and the second semiconductor device 107, and all such processes arefully intended to be included within the scope of the embodiments.

FIG. 1C illustrates formation of first vias 135 in contact with thefirst external connectors 115 on the first semiconductor device 105 andin contact with the second external connectors 127 on the secondsemiconductor device 107. In an embodiment the process to form the firstvias 135 may be performed using, e.g., a masking and plating process ora damascene process. In an embodiment in which a masking and platingprocess is utilized to form the first vias 135, the masking and platingprocess may be initiated by first forming a first seed layer 133. In anembodiment the first seed layer 133 is a thin layer of a conductivematerial that aids in the formation of a thicker layer during subsequentprocessing steps, such as titanium, copper, molybdenum, tungsten,titanium nitride, titanium tungsten, combinations thereof, or the like.In some embodiments, the first seed layer 133 comprises a titanium layerand a copper layer over the titanium layer. The first seed layer 133 maybe formed using, for example, PVD, evaporation, or PECVD processes, orthe like. The first seed layer 133 may be formed to have almost straightsidewalls and a thickness of between about 0.3 μm and about 1 μm, suchas about 0.5 μm.

FIG. 1C also illustrates a placement and patterning of a photoresist 131over the first seed layer 133. In an embodiment the photoresist 131 maybe placed on the first seed layer 133 using, e.g., a spin coatingtechnique. Once in place, the photoresist 131 may then be patterned byexposing the photoresist to a patterned energy source (e.g., a patternedlight source) so as to induce a chemical reaction, thereby inducing aphysical change in those portions of the photoresist 131 exposed to thepatterned light source. A developer is then applied to the exposedphotoresist 131 to take advantage of the physical changes andselectively remove either the exposed portion of the photoresist 131 orthe unexposed portion of the photoresist 131, depending upon the desiredpattern.

In an embodiment the first vias 135 are formed within the photoresist131. In an embodiment the first vias 135 comprise one or more conductivematerials, such as copper, tungsten, other conductive metals, or thelike, and may be formed, for example, by electroplating, electrolessplating, or the like. In an embodiment, an electroplating process isused wherein the first seed layer 133 and the photoresist 131 aresubmerged or immersed in an electroplating solution. The first seedlayer 133 surface is electrically connected to the negative side of anexternal DC power supply such that the first seed layer 133 functions asthe cathode in the electroplating process. A solid conductive anode,such as a copper anode, is also immersed in the solution and is attachedto the positive side of the power supply. The atoms from the anode aredissolved into the solution, from which the cathode, e.g., the firstseed layer 133, acquires the dissolved atoms, thereby plating theexposed conductive areas of the first seed layer 133 within the openingof the photoresist 131.

In another embodiment, the first vias 135 include three layers ofconductive materials, such as a layer of titanium, a layer of copper,and a layer of nickel. However, one of ordinary skill in the art willrecognize that there are many suitable arrangements of materials andlayers, such as an arrangement of chrome/chrome-copperalloy/copper/gold, an arrangement of titanium/titanium tungsten/copper,or an arrangement of copper/nickel/gold. Any suitable materials orlayers of material that may be used for the first vias 135 are fullyintended to be included within the scope of the current application.

FIG. 1D illustrates that once the first vias 135 have been formed usingthe photoresist 131 and the first seed layer 133, the photoresist 131may be removed using a suitable removal process. In an embodiment, aplasma ashing process may be used to remove the photoresist 131, wherebythe temperature of the photoresist 131 may be increased until thephotoresist 131 experiences a thermal decomposition and may be removed.However, any other suitable process, such as a wet strip, mayalternatively be utilized. The removal of the photoresist 131 may exposethe underlying portions of the first seed layer 133.

FIG. 1E illustrates a removal of the exposed portions of the first seedlayer 133. In an embodiment the exposed portions of the first seed layer133 (e.g., those portions that are not covered by the first vias 135)may be removed by, for example, a wet or dry etching process. Forexample, in a dry etching process reactants may be directed towards thefirst seed layer 133 using the first vias 135 as masks. In anotherembodiment, etchants may be sprayed or otherwise put into contact withthe first seed layer 133 in order to remove the exposed portions of thefirst seed layer 133.

FIG. 1E additionally illustrates that, once the first seed layer 133 isetched, the first vias 135 are coated with a first dielectric material137. In an embodiment the first dielectric material 137 may be apolymer, such as polybenzoxazole (PBO), polyimide, benzocyclobutene(BCB), or the like. In other embodiments, the first dielectric material137 is formed of a nitride such as silicon nitride; an oxide such assilicon oxide, phosphosilicate glass (PSG), borosilicate glass (BSG),boron-doped phosphosilicate glass (BPSG), or the like. The firstdielectric material 137 may be formed by any acceptable depositionprocess, such as spin coating, chemical vapor deposition (CVD),laminating, the like, or a combination thereof.

FIG. 1F illustrates that, once the first dielectric material 137 iscured, the first dielectric material 137 may be planarized. Theplanarizing may be performed, e.g., using a mechanical grinding,chemical approaches, or chemical mechanical polishing (CMP) processwhereby chemical etchants and abrasives are utilized to react and grindaway the first dielectric material 137 until the first vias 135 havebeen exposed. As such, the first dielectric material 137 and the firstvias 135 may have a planar surface.

However, while the CMP, mechanical grinding, or chemical approachprocesses described above are presented as illustrative embodiments, itis not intended to be limiting to the embodiments. Any other suitableremoval process may alternatively be used to planarize the firstdielectric material 137 and expose the first vias 135. For example, aseries of chemical etches may be utilized. This process and any othersuitable process may alternatively be utilized to planarize the firstdielectric material 137 and expose the first vias 135, and all suchprocesses are fully intended to be included within the scope of theembodiments.

FIG. 1G illustrates an embodiment in which the first vias 135 are formedusing a damascene process. In this embodiment the first seed layer 133is not deposited and the first dielectric material 137 may be depositedprior to the formation of the first vias 135. In an embodiment the firstdielectric material 137 may be deposited as described above (e.g.,through a chemical vapor deposition process), and then planarized tohelp ensure that a flat surface is ready for further manufacturing.

Once the first dielectric material 137 is deposited and planarized, thefirst dielectric material 137 may be patterned to form openings for thefirst vias 135. In an embodiment the first dielectric material 137 maybe patterned by initially applying a photoresist over the unpatternedfirst dielectric material 137, and then exposing and developing thephotoresist in order to form the desired pattern for the first vias 135.Once the photoresist is patterned, the pattern is then transferred tothe underlying first dielectric material 137 using, e.g., an anisotropicetching process such as a reactive ion etch in order to expose theunderlying second external connectors 127. However, any suitable methodof patterning the first dielectric material 137 may be utilized.

After the second external connectors 127 have been exposed, the openingsthrough the first dielectric material 137 are then filled with aconductive material. In an embodiment a seed layer may be depositedalong with one or more barrier layers. In an embodiment the seed layermay be similar to the first seed layer 133, such as by being a titaniumlayer and a copper layer over the titanium layer that have beendeposited using, e.g., physical vapor deposition to line the bottom andsidewall surfaces of the openings. However, any suitable materials anddeposition process may be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the first dielectric layer 137. However, any suitablematerial and process may be utilized in order to fill the openings withthe conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thefirst dielectric material 137 are removed to form the first vias 135. Inan embodiment the excess portions may be removed using, e.g., aplanarizing process such as a chemical mechanical polishing process, agrinding process, other chemical processes, combinations of these, orthe like. However, any suitable process of embedding the conductivematerial into the first dielectric material 137 and forming the firstvias 135 may be utilized.

In an embodiment, once the first vias 135 have been planarized, thefirst vias 135 may be formed to have a first width W₁ of between about0.1 μm and about 20 μm, such as about 5 μm. Similarly, the first vias135 may be formed to have a first height H₁ (over the first seed layer133) of between about 0.1 μm and about 20 μm, such as about 5 μm.However, any suitable dimensions may be utilized.

FIG. 2A illustrates the beginning of a formation of a firstmetallization layer 205 (otherwise known as a redistribution layer) overthe first vias 135 using either a plating process or a damasceneprocess. In an embodiment in which a plating process is utilized, asecond seed layer 201 is formed over the first dielectric material 137.The second seed layer 201 may be similar to the first seed layer 133.For example, the second seed layer 201 may be created using processessuch as sputtering, evaporation, or PECVD processes, depending upon thedesired materials. The second seed layer 201 may be formed to have athickness of between about 0.01 μm and about 1 μm, such as about 0.5 μm.

FIG. 2A also illustrates a placement and patterning of a secondphotoresist 203 over the second seed layer 201. In an embodiment thesecond photoresist 203 may be a dry or wet photoresist and may be placedon the second seed layer 201 using, e.g., a spin coating technique. Oncein place, the second photoresist 203 may then be patterned by exposingthe second photoresist 203 to a patterned energy source (e.g., apatterned light source) so as to induce a chemical reaction, therebyinducing a physical change in those portions of the second photoresist203 exposed to the patterned light source. A developer is then appliedto the exposed second photoresist 203 to take advantage of the physicalchanges and selectively remove either the exposed portion of the secondphotoresist 203 or the unexposed portion of the second photoresist 203,depending upon the desired pattern.

Once the second photoresist 203 is patterned, the first metallizationlayer 205 may be formed on the second seed layer 201 within the secondphotoresist 203. In an embodiment the first metallization layer 205comprises one or more conductive materials, such as copper, tungsten,other conductive metals, or the like, and may be formed, for example, byelectroplating, electroless plating, or the like. In an embodiment, anelectroplating process is used wherein the second seed layer 201 and thesecond photoresist 203 are submerged or immersed in an electroplatingsolution. The second seed layer 201 surface is electrically connected tothe negative side of an external DC power supply such that the secondseed layer 201 functions as the cathode in the electroplating processwhen a current is run through the second seed layer 201. A solidconductive anode, such as a copper anode, is also immersed in thesolution and is attached to the positive side of the power supply. Theatoms from the anode are dissolved into the solution, from which thecathode, e.g., the second seed layer 201, acquires the dissolved atoms,thereby plating the exposed conductive areas of the second seed layer201 within the opening of the second photoresist 203.

In another embodiment, the first metallization layer 205 includes threelayers of conductive materials, such as a layer of titanium, a layer ofcopper, and a layer of nickel. However, one of ordinary skill in the artwill recognize that there are many suitable arrangements of materialsand layers, such as an arrangement of chrome/chrome-copperalloy/copper/gold, an arrangement of titanium/titanium tungsten/copper,or an arrangement of copper/nickel/gold. Any suitable materials orlayers of material that may be used for the first metallization layer205 are fully intended to be included within the scope of the currentapplication.

In an embodiment, once the first metallization layer 205 is formed, thefirst metallization layer 205 may be formed to have a second width W₂that is larger than the first width W₁ (of the first vias 135), and maybe between about 0.1 μm and about 10 μm, such as about 0.7 μm.Similarly, the first metallization layer 205 may be formed to have asecond height H₂ (over the second seed layer 201) of between about 0.05μm and about 20 μm, such as about 1 μm. However, any suitable dimensionsmay be utilized.

Additionally, in some embodiments the first metallization layer 205 maybe formed to include a pad portion for connection with an overlying via(e.g., the second vias 209). The pad portion may be wider than theremaining portion of the first metallization layer 205 and may also beformed to be larger than or equal to the overlying via size. However,any suitable dimensions may be utilized.

FIG. 2B illustrates that, once the first metallization layer 205 isformed, the second photoresist 203 may be removed using a suitableremoval process. In an embodiment, a plasma ashing process may be usedto remove the second photoresist 203, whereby the temperature of thesecond photoresist 203 may be increased until the second photoresist 203experiences a thermal decomposition and may be removed. However, anyother suitable process, such as a wet strip, may alternatively beutilized.

Optionally, at this point the first metallization layer 205 may betreated. In a particular embodiment the first metallization layer 205may be treated in order to prepare the first metallization layer 205 forthe formation of second vias 209 (discussed further below). In anembodiment the surface treatment may be a descum treatment such as aplasma treatment wherein the surface of the first metallization layer205 is exposed to a plasma of, e.g., argon, nitrogen, oxygen or a mixedAr/N₂/O₂ ambient environment in order to improve the interface adhesionbetween the first metallization layer 205 and overlying layers (e.g.,the second vias 209). However, any suitable surface treatment may beutilized.

FIG. 2C illustrates a placement of a third photoresist 207 over thefirst metallization layer 205. In an embodiment the third photoresist207 may be a dry or wet photoresist and may be placed on the firstmetallization layer 205 using, e.g., a spin coating technique. Once inplace, the third photoresist 207 may then be patterned by exposing thethird photoresist 207 to a patterned energy source (e.g., a patternedlight source) so as to induce a chemical reaction, thereby inducing aphysical change in those portions of the third photoresist 207 exposedto the patterned light source. A developer is then applied to theexposed third photoresist 207 to take advantage of the physical changesand selectively remove either the exposed portion of the thirdphotoresist 207 or the unexposed portion of the third photoresist 207,depending upon the desired pattern.

In another embodiment the second photoresist 203 is not removed prior tothe placement of the third photoresist 207. Rather, the thirdphotoresist 207 is placed over the second photoresist 203 and into theopenings formed by the second photoresist 203. Such an embodiment allowsfor a similar process without the need of the additional ashing processto remove the second photoresist 203.

In an embodiment the third photoresist 207 is developed to form apattern for second vias 209 which exposes a top surface of the firstmetallization layer 205, wherein the pattern will include straight andvertical or almost vertical sidewalls through the third photoresist 207.Once the first metallization layer 205 is exposed through the thirdphotoresist 207, the second vias 209 may be formed within the thirdphotoresist 207. In an embodiment the second vias 209 comprise one ormore conductive materials, such as copper, tungsten, other conductivemetals, or the like, and may be formed, for example, by electroplating,electroless plating, or the like. In an embodiment, an electroplatingprocess is used wherein the first metallization layer 205 and the thirdphotoresist 207 are submerged or immersed in an electroplating solution.The second seed layer 201 (and, thereby, also the first metallizationlayer 205) is electrically connected to the negative side of an externalDC power supply such that the first metallization layer 205 functions asthe cathode in the electroplating process when a current is again runthrough the second seed layer 201. A solid conductive anode, such as acopper anode, is also immersed in the solution and is attached to thepositive side of the power supply. The atoms from the anode aredissolved into the solution, from which the cathode, e.g., the combinedsecond seed layer 201 and first metallization layer 205, acquires thedissolved atoms, thereby plating the exposed conductive areas of thefirst metallization layer 205 within the opening of the thirdphotoresist 207 such that the second vias 209 take on the shape of theopening through the photoresist, including the straight sidewalls.

In another embodiment, the second vias 209 include three layers ofconductive materials, such as a layer of titanium, a layer of copper,and a layer of nickel. However, one of ordinary skill in the art willrecognize that there are many suitable arrangements of materials andlayers, such as an arrangement of chrome/chrome-copperalloy/copper/gold, an arrangement of titanium/titanium tungsten/copper,or an arrangement of copper/nickel/gold. Any suitable materials orlayers of material that may be used for the second vias 209 are fullyintended to be included within the scope of the current application.

By forming the second vias 209 as described, the second vias 209 can beformed directly onto the first metallization layer 205. This allows thesecond vias 209 to be formed without the need for yet another seedlayer. As such, both the first metallization layer 205 and the secondvias 209 may be formed using a single seed layer (e.g., the second seedlayer 201). Additionally, the second vias 209 are fully or partiallylanded on the material of the first metallization layer 205.

In an embodiment, once the second vias 209 have been formed on the firstmetallization layer 205, the second vias 209 may be formed to have athird width W₃ that is smaller than the second width W₂ (of the firstmetallization layer 205) and may be between about 0.1 μm and about 20μm, such as about 5 μm. Similarly, the second vias 209 may be formed tohave a third height H₃ of between about 0.1 μm and about 20 μm, such asabout 5 μm. However, any suitable dimensions may be utilized.

FIG. 2D illustrates that, once the second vias 209 have been formed, thethird photoresist 207 may be removed using a suitable removal process.In an embodiment, a plasma ashing process may be used to remove thethird photoresist 207, whereby the temperature of the third photoresist207 may be increased until the third photoresist 207 experiences athermal decomposition and may be removed. However, any other suitableprocess, such as a wet strip, may alternatively be utilized.

FIG. 2D additionally illustrates a removal of the exposed portions ofthe second seed layer 201. In an embodiment the exposed portions of thesecond seed layer 201 may be removed by, for example, a wet or dryetching process. For example, in a dry etching process reactants may bedirected towards the second seed layer 201 using the first metallizationlayer 205 as masks. In another embodiment, etchants may be sprayed orotherwise put into contact with the second seed layer 201 in order toremove the exposed portions of the second seed layer 201.

FIG. 2E illustrates that, once the second seed layer 201 is etched, thefirst metallization layer 205 and the second vias 209 are coated with asecond dielectric material 211. In an embodiment the second dielectricmaterial 211 may be similar to first dielectric material 137 (describedabove with respect to FIG. 1E), although any suitable material, such aspolyimide or a polyimide derivative, may be utilized. The seconddielectric material 211 may be placed using, e.g., a spin-coatingprocess to a thickness of greater than about 1 μm or greater than about20 μm, such as about 7 μm, although any suitable method and thicknessmay alternatively be used. Once in place, the second dielectric material211 may be cured.

FIG. 2F illustrates that, once the second dielectric material 211 iscured, the second dielectric material 211 may be planarized. Theplanarizing may be performed, e.g., using a mechanical grinding,chemical approaches, or chemical mechanical polishing (CMP) processwhereby chemical etchants and abrasives are utilized to react and grindaway the second dielectric material 211 until the second vias 209 havebeen exposed. As such, the second dielectric material 211 and the secondvias 209 may have a planar surface.

However, while the CMP process described above is presented as oneillustrative embodiment, it is not intended to be limiting to theembodiments. Any other suitable removal process may alternatively beused to planarize the second dielectric material 211 and expose thesecond vias 209. For example, a series of chemical etches may beutilized. This process and any other suitable process may alternativelybe utilized to planarize the second dielectric material 211 and exposethe second vias 209, and all such processes are fully intended to beincluded within the scope of the embodiments.

FIG. 2G illustrates the embodiment in which the first metallizationlayer 205 and the second vias 209 are formed using a damascene process.In this embodiment, instead of the second seed layer 201 being formedfirst, the second dielectric material 211 is initially depositeddirectly onto the first dielectric material 137 and the first vias 135.For example, the second dielectric material 211 may be formed as apolyimide derivative, and using e.g., a spin-coating process. However,any suitable material and method of deposition may be utilized.

Once the second dielectric material 211 is placed, the second dielectricmaterial 211 may be patterned in order to form the desired shape for thefirst metallization layer 205. In an embodiment the second dielectricmaterial 211 may be patterned by initially applying and then exposingand developing a photoresist in order to form a pattern in the shapedesired for first metallization layer 205.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second dielectricmaterial 211. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second dielectric material 211 andexposes the underlying first vias 135. However, any suitable process maybe used to transfer the pattern.

After the first vias 135 have been exposed, the openings through thesecond dielectric material 211 are then filled with a conductivematerial. In an embodiment a seed layer may be deposited along with oneor more barrier layers. In an embodiment the seed layer may be similarto the first seed layer 133, such as by being a titanium layer and acopper layer over the titanium layer that have been deposited using,e.g., physical vapor deposition to line the bottom and sidewall surfacesof the openings. However, any suitable materials and deposition processmay be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second dielectric material 211. However, anysuitable material and process may be utilized in order to fill theopenings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond dielectric material 211 are removed to form the firstmetallization layer 205. In an embodiment the excess portions may beremoved using, e.g., a planarizing process such as a chemical mechanicalpolishing process, a grinding process, other chemical processes,combinations of these, or the like. However, any suitable process ofembedding the conductive material into the second dielectric material211 and forming the first metallization layer 205 may be utilized.

FIG. 2G additionally illustrates that, once the first metallizationlayer 205 is formed, the second vias 209 may also be formed utilizing adamascene process. For example, once the first metallization layer 205is formed, a second via dielectric layer 213 may be deposited over thefirst metallization layer 205. In an embodiment the second viadielectric layer 213 may be a similar material and deposited using asimilar process as the second dielectric material 211, such as by beingformed as a polyimide derivative, and using, e.g., a spin-coatingprocess. However, any suitable material and method of deposition may beutilized.

Once the second via dielectric layer 213 is placed, the second viadielectric layer 213 may be patterned in order to form the desired shapefor the second vias 209. In an embodiment the second via dielectriclayer 213 may be patterned by initially applying and then exposing anddeveloping a photoresist in order to form a pattern in the shape desiredfor second vias 209.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second via dielectriclayer 213. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second via dielectric layer 213 andexposes the underlying first metallization layer 205. However, anysuitable process may be used to transfer the pattern.

After the first metallization layer 205 is exposed, the openings throughthe second via dielectric layer 213 are then filled with a conductivematerial. In an embodiment a seed layer may be deposited along with oneor more barrier layers. In an embodiment the seed layer may be similarto the first seed layer 133, such as by being a titanium layer and acopper layer over the titanium layer that have been deposited using,e.g., physical vapor deposition to line the bottom and sidewall surfacesof the openings. However, any suitable materials and deposition processmay be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second via dielectric layer 213. However, anysuitable material and process may be utilized in order to fill theopenings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond via dielectric layer 213 are removed to form the second vias 209.In an embodiment the excess portions may be removed using, e.g., aplanarizing process such as a chemical mechanical polishing process, agrinding process, other chemical processes, combinations of these, orthe like. However, any suitable process of embedding the conductivematerial into the second via dielectric layer 213 and forming the secondvias 209 may be utilized.

FIG. 3 illustrates that, once the first metallization layer 205 and thesecond vias 209 have been formed, similar processes may be repeated inorder to form a second metallization layer 307 and a third via 309 (bothformed using a single seed layer) and a third metallization layer 311,each within different dielectric layers. Further, once the thirdmetallization layer 311 is formed a passivation layer 301 may be formedand patterned, underbump metallizations 303 may be formed, and thirdexternal connectors 305 may be placed. In an embodiment the passivationlayer 301 may be made of one or more suitable dielectric materials suchas polybenzoxazole (PBO), although any suitable material, such aspolyimide or a polyimide derivative, silicon nitride, silicon oxide, orthe like, may be utilized. The passivation layer 301 may be placedusing, e.g., a spin-coating process to a thickness of between about 5 μmand about 25 μm, such as about 7 μm, although any suitable method andthickness may alternatively be used.

In an embodiment the underbump metallizations 303 may each comprisethree layers of conductive materials, such as a layer of titanium, alayer of copper, and a layer of nickel. However, one of ordinary skillin the art will recognize that there are many suitable arrangements ofmaterials and layers, such as an arrangement of chrome/chrome-copperalloy/copper/gold, an arrangement of titanium/titanium tungsten/copper,or an arrangement of copper/nickel/gold, that are suitable for theformation of the underbump metallizations 303. Any suitable materials orlayers of material that may be used for the underbump metallizations 303are fully intended to be included within the scope of the embodiments.

In an embodiment the underbump metallizations 303 are created using aplating process, such as electrochemical plating, although otherprocesses of formation, such as sputtering, evaporation, or PECVDprocess, may be used depending upon the desired materials. The underbumpmetallizations 303 may be formed to have a thickness of between about0.7 μm and about 10 μm, such as about 5 μm.

Once the underbump metallizations 303 have been formed, the thirdexternal connectors 305 may be BGA connectors, copper bumps, solderballs, metal pillars, controlled collapse chip connection (C4) bumps,micro bumps, electroless nickel-electroless palladium-immersion goldtechnique (ENEPIG) formed bumps, combinations of these, or the like. Theconductive connectors may include a conductive material such as solder,copper, aluminum, gold, nickel, silver, palladium, tin, the like, or acombination thereof. However, any suitable material or combination ofmaterials may be utilized.

Additionally, while the embodiments described above with respect toFIGS. 1-3 describe an embodiment which utilizes the first metallizationlayer 205 and the second metallization layer 307, this number ofmetallization layers (and their respective vias) is intended to beillustrative only and is not intended to be limiting upon theembodiments. Rather, any suitable number of metallization layers andvias may be utilized, and all such numbers, such as 3, 4, 5 or morelayers, are fully intended to be included within the scope of theembodiments.

FIG. 4 illustrates other embodiments which may be utilized. For example,in the embodiment illustrated in FIG. 4, a through InFO via (TIV) 401may be utilized in order to provide connectivity from one side of theencapsulant 129 to another side of the encapsulant 129. In an embodimentthe TIV 401 may be formed on the polymer layer 103 prior to theplacement of the first semiconductor device 105 and the secondsemiconductor device 107. For example, a seed layer may be placed on thepolymer layer 103, and a photoresist may be placed and patterned overthe seed layer to form openings in the desired shape of the TIVs 401.Once the photoresist is patterned, the TIV 401 may be plated within theopenings and onto the exposed seed layer. After the TIV 401 is formed,the photoresist may be removed and the seed layer etched to leave behindthe TIVs 401.

Once the TIVs 401 have been formed, the process may continue asdescribed above to place the first semiconductor device 105 and thesecond semiconductor device 107. Additionally, the first vias 135, thefirst metallization layer 205, and the second vias 209 (along with aremainder of the metallization layers) may be formed. However, insteadof some of the first vias 135 being connected to the encapsulant 129(and thereby being dummy vias), the first vias 135 may be connected tothe TIV 401, thereby providing electrical connectivity from one side ofthe encapsulant 129 to a second side of the encapsulant 129.

Additionally, FIG. 4 illustrates that a third passivation layer 403 maybe formed between the first passivation layer 113 and the first externalconnectors 115. The third passivation layer 403 may be made of one ormore suitable dielectric materials such as polybenzoxazole (PBO),although any suitable material, such as silicon nitride, silicon oxide,polyimide or a polyimide derivative, may alternatively be utilized. Thethird passivation layer 403 may be placed using, e.g., a spin-coatingprocess to a thickness of between about 5 μm and about 25 μm, such asabout 7 μm, although any suitable method and thickness may alternativelybe used. Once in place, the third passivation layer 403 may be patternedprior to the formation of the first external connectors 115.

FIG. 5 illustrates another embodiment which utilizes the thirdpassivation layer 403. However, in this embodiment the TIVs 401 are notformed. As such, some of the first vias 135 are formed over theencapsulant 129 and are not electrically connected to the firstsemiconductor device 105 or the second semiconductor device 107.Accordingly, the unconnected first vias 135 are dummy structures thatare electrically isolated.

FIG. 6 illustrates another embodiment which utilizes the TIVs 401.However, in this embodiment the third passivation layer 403 is notformed. As such, some of the first vias 135 are formed in electricalconnection with the TIVs 401. Such connections allow electricalconduction to the opposite side of the encapsulant 129.

FIGS. 7A-7F illustrate another embodiment in which the second vias 209,instead of being formed fully landed on the first metallization layer205, are formed being partially landed on the first metallization layer205. In this embodiment, FIGS. 7A and 7B are similar to FIGS. 2A-2B asdescribed above. As such, this description is not repeated.

FIG. 7C illustrates a deposition and patterning of the third photoresist207 over the first metallization layer 205. In an embodiment the thirdphotoresist 207 may be deposited or placed and patterned as describedabove with respect to FIG. 2C, such as by exposing a developing thethird photoresist 207 to form a pattern with straight and vertical oralmost vertical sidewalls. However, in this embodiment, instead of beingpatterned to expose a top surface of the first metallization layer 205,the third photoresist 207 is patterned in order to expose both a portionof the top surface of the first metallization layer 205 and also exposea sidewall of the first metallization layer 205. Additionally, by fullyexposing the sidewall of the first metallization layer 205, theunderlying second seed layer 201 is also partially exposed as well.

In an embodiment the third photoresist 207 may be patterned such thatthe surface of the first metallization layer 205 that is exposed has afourth width W₄ of between about 0.1 μm and about 20 μm, such as about 5μm. Similarly, the third photoresist 207 is patterned such that thesurface of the second seed layer 201 that is exposed has a fifth widthW₅ of between about 0.1 μm and about 20 μm, such as about 5 μm. However,any suitable dimensions may be utilized.

FIG. 7D illustrates a formation of the second vias 209 within the thirdphotoresist 207. In an embodiment the formation of the second vias 209may be performed as described above with respect to FIG. 2C. Forexample, the second vias 209 may be formed using an electroplatingprocess which at least partially fills the openings in the thirdphotoresist 207, wherein the first metallization layer 205 and thesecond vias 209 are formed using the same seed layer and in which thesecond vias 209 take on the shape of the pattern of the thirdphotoresist 207, such as having straight and vertical or almost verticalsidewalls. In this embodiment, however, the material for the second vias209 not only covers the top surface of the first metallization layer205, but also covers at least one side surface of the firstmetallization layer 205 and is in physical contact with a portion of thesecond seed layer 201.

In this embodiment the second vias 209 may have a sixth width W₆ ofbetween about 0.1 μm and about 20 μm, such as about 5 μm. Similarly, thesecond vias 209 in this embodiment may have a fourth height H₄ (over thesecond seed layer 201) of between about 0.01 μm and about 20 μm, such asabout 3 μm, while the second vias 209 may have a fifth height H₅ (overthe first metallization layer 205) of between about 0.05 μm and about 20μm, such as about 5 μm. However, any suitable dimensions may beutilized.

FIG. 7D additionally illustrates a removal of the third photoresist 207.In an embodiment the third photoresist 207 may be removed as describedabove with respect to FIG. 2D. For example, an ashing process may beutilized to remove the third photoresist 207. However, any suitableprocess may be utilized to remove the third photoresist 207.

Finally, FIG. 7D also illustrates an etching of the second seed layer201. In an embodiment the second seed layer 201 may be etched asdescribed above with respect to FIG. 2D. For example, a wet or dryetching process may be utilized to remove the exposed portions of thesecond seed layer 201. However, any suitable process may be utilized.

FIGS. 7E and 7F illustrate the placement and planarization of the seconddielectric material 211 over the second vias 209. In an embodiment thesecond dielectric material 211 may be placed and planarized as describedabove with respect to FIGS. 2E and 2F. For example, the seconddielectric material 211 may be deposited and cured, and then a CMP,mechanical grinding, or chemical approach processes may be utilized toplanarize the second dielectric material 211 and expose the second vias209. However, any suitable process may be utilized.

FIG. 7G illustrates the embodiment in which the first metallizationlayer 205 and the second vias 209 are formed using a damascene processto be partially landed. In this embodiment, instead of the second seedlayer 201 being formed first, the second dielectric material 211 isinitially deposited directly onto the first dielectric material 137 andthe first vias 135. For example, the second dielectric material 211 maybe formed as a polyimide derivative, and using e.g., a spin-coatingprocess. However, any suitable material and method of deposition may beutilized.

Once the second dielectric material 211 is placed, the second dielectricmaterial 211 may be patterned in order to form the desired shape for thefirst metallization layer 205. In an embodiment the second dielectricmaterial 211 may be patterned by initially applying and then exposingand developing a photoresist in order to form a pattern in the shapedesired for first metallization layer 205.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second dielectricmaterial 211. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second dielectric material 211 andexposes the underlying first vias 135. However, any suitable process maybe used to transfer the pattern.

After the first vias 135 have been exposed, the openings through thesecond dielectric material 211 are then filled with a conductivematerial. In an embodiment a seed layer may be deposited along with oneor more barrier layers. In an embodiment the seed layer may be similarto the first seed layer 133, such as by being a titanium layer and acopper layer over the titanium layer that have been deposited using,e.g., physical vapor deposition to line the bottom and sidewall surfacesof the openings. However, any suitable materials and deposition processmay be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second dielectric material 211. However, anysuitable material and process may be utilized in order to fill theopenings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond dielectric material 211 are removed to form the firstmetallization layer 205. In an embodiment the excess portions may beremoved using, e.g., a planarizing process such as a chemical mechanicalpolishing process, a grinding process, other chemical processes,combinations of these, or the like. However, any suitable process ofembedding the conductive material into the second dielectric material211 and forming the first metallization layer 205 may be utilized.

FIG. 7G additionally illustrates that, once the first metallizationlayer 205 is formed, the second vias 209 may also be formed utilizing adamascene process. For example, once the first metallization layer 205is formed, the second via dielectric layer 213 may be deposited over thefirst metallization layer 205. In an embodiment the second viadielectric layer 213 may be a similar material and deposited using asimilar process as the second dielectric material 211, such as by beingformed as a polyimide derivative, and using, e.g., a spin-coatingprocess. However, any suitable material and method of deposition may beutilized.

Once the second via dielectric layer 213 is placed, the second viadielectric layer 213 may be patterned in order to form the desired shapefor the second vias 209. In an embodiment the second via dielectriclayer 213 may be patterned by initially applying and then exposing anddeveloping a photoresist in order to form a pattern in the shape desiredfor second vias 209.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second via dielectriclayer 213. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second via dielectric layer 213 andexposes the underlying first metallization layer 205. However, anysuitable process may be used to transfer the pattern.

Additionally in this embodiment, the anisotropic etching process is notstopped when the top surface of the underlying first metallization layer205 is exposed. Rather, the etching process is continued so that aportion of the second dielectric material 211 is removed to expose asidewall of the first metallization layer 205 and, in some embodiments,expose the first dielectric material 137.

After the first metallization layer 205 is exposed, the openings throughthe second via dielectric layer 213 and the second dielectric material211 are then filled with a conductive material. In an embodiment a seedlayer may be deposited along with one or more barrier layers. In anembodiment the seed layer may be similar to the first seed layer 133,such as by being a titanium layer and a copper layer over the titaniumlayer that have been deposited using, e.g., physical vapor deposition toline the bottom and sidewall surfaces of the openings. However, anysuitable materials and deposition process may be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second via dielectric layer 213 and the seconddielectric material 211. However, any suitable material and process maybe utilized in order to fill the openings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond via dielectric layer 213 and the second dielectric material 211are removed to form the second vias 209. In an embodiment the excessportions may be removed using, e.g., a planarizing process such as achemical mechanical polishing process, a grinding process, otherchemical processes, combinations of these, or the like. However, anysuitable process of embedding the conductive material into the secondvia dielectric layer 213 and the second dielectric material 211 andforming the second vias 209 may be utilized.

FIG. 8 illustrates that, once the first metallization layer 205 and thesecond vias 209 have been formed in this embodiment, similar processesmay be repeated in order to form the second metallization layer 307 andthe third via 309 (both formed using a single seed layer) and the thirdmetallization layer 311, all with the vias being partially landed on theunderlying metallization layer. Further, once the third metallizationlayer 311 is formed the passivation layer 301 may be formed andpatterned, the underbump metallizations 303 may be formed, and the thirdexternal connectors 305 may be placed as described above with respect toFIG. 3. However, any suitable methods and materials may be utilized.

FIG. 9 illustrates another embodiment in which the second vias 209 (orany suitable via) is formed as being partially landed on the firstmetallization layer 205. In this embodiment, however, the TIVs 401 areadditionally formed in order to electrically connect the first vias 135to an opposite side of the encapsulant 129. In an embodiment the TIVs401 may be formed as described above with respect to FIG. 4. Forexample, the TIVs may be formed using an electroplating process beforethe first semiconductor device 105 and the second semiconductor device107 are placed on the polymer layer 103. However, any suitable method offorming the TIVs 401 are fully intended to be included within the scopeof the embodiments.

FIG. 10 illustrates an embodiment in which, in addition to the TIVs 401as described in FIG. 9, the third passivation layer 403 is also formedbetween the first passivation layer 113 and the first externalconnectors 115. In this embodiment the third passivation layer 403 maybe formed as described above with respect to FIG. 4. However, anysuitable method and materials may be utilized.

FIG. 11 illustrates an embodiment in which the third passivation layer403 is utilized without the presence of the TIVs 401. In this embodimentsome of the first vias 135, instead of being electrically connected tothe TIVs 401, are instead utilized as dummy materials to providestructural support.

FIGS. 12A-12F illustrate another embodiment in which the second vias209, instead of being formed fully landed on the first metallizationlayer 205, are formed being partially landed on the first metallizationlayer 205. In this embodiment, FIGS. 12A and 12B are similar to FIGS.2A-2B as described above. As such, this description is not repeated.

FIG. 12C illustrates a deposition and patterning of the thirdphotoresist 207 over the first metallization layer 205. In an embodimentthe third photoresist 207 may be deposited or placed and patterned asdescribed above with respect to FIG. 2C, such as by being exposed anddeveloped to form a pattern with straight and vertical or almostvertical sidewalls. However, in this embodiment, instead of beingpatterned to expose a top surface of the first metallization layer 205,the third photoresist 207 is patterned in order to expose both a portionof the top surface of the first metallization layer 205 and also exposea portion (but not all) of a sidewall of the first metallization layer205. Such an exposure of the sidewalls of the first metallization layer205 may be performed using a timed development process or, in anotherembodiment, may be performed using a controlled exposure that exposes aportion, but not all, of the depth of the third photoresist 207.Additionally in this embodiment, the second seed layer 201 remains fullycovered by either the first metallization layer 205 or the thirdphotoresist 207.

FIG. 12D illustrates a formation of the second vias 209 within the thirdphotoresist 207. In an embodiment the formation of the second vias 209may be performed as described above with respect to FIG. 2C. Forexample, the second vias 209 may be formed using an electroplatingprocess which at least partially fills the openings in the thirdphotoresist 207, wherein the first metallization layer 205 and thesecond vias 209 are formed using the same seed layer, wherein the secondvias 209 take on the shape of the pattern, including having straight andvertical or almost vertical sidewalls. In this embodiment, however, thematerial for the second vias 209 not only covers the top surface of thefirst metallization layer 205, but also covers a portion (but not all)of the side surface of the first metallization layer 205.

For example, in this embodiment, the third photoresist 207 may bepatterned such that the surface of the first metallization layer 205that is exposed has the fourth width W₄ of between about 0.1 μm andabout 20 μm, such as about 5 μm, and a portion of the third photoresist207 removed adjacent to the first metallization layer 205 has the fifthwidth W₅ of between about 0.1 μm and about 20 μm, such as about 5 μm.Additionally, a portion of the sidewall of the first metallization layer205 may have a sixth height H₆ of between about 0.01 μm and about 10 μm,such as about 1 μm. However, any suitable dimensions may be utilized.

FIG. 12D additionally illustrates a removal of the third photoresist207. In an embodiment the third photoresist 207 may be removed asdescribed above with respect to FIG. 2D. For example, an ashing processmay be utilized to remove the third photoresist 207. However, anysuitable process may be utilized to remove the third photoresist 207.

In this embodiment the second vias 209 may have the sixth width W₆ ofbetween about 0.1 μm and about 20 μm, such as about 5 μm. Similarly, thesecond vias 209 in this embodiment may have an seventh height H₇ (overthe second seed layer 201 and along the sidewall of the firstmetallization layer 205) of between about 0.01 μm and about 20 μm, suchas about 5 μm, while the second vias 209 may have a eighth height H₈(over the first metallization layer 205) of between about 0.01 μm andabout 20 μm, such as about 3 μm. However, any suitable dimensions may beutilized.

Finally, FIG. 12D also illustrates an etching of the second seed layer201. In an embodiment the second seed layer 201 may be etched asdescribed above with respect to FIG. 2D. For example, a wet or dryetching process may be utilized to remove the exposed portions of thesecond seed layer 201. Because of the removal of the second seed layer201 from beneath a portion of the second vias 209, the second vias 209may be separated from the first dielectric material 137 by a firstdistance D₁ of between about 0.01 μm and about 20 μm, such as about 5μm. However, any suitable process and dimensions may be utilized.

FIGS. 12E and 12F illustrate the placement and planarization of thesecond dielectric material 211 over the second vias 209. In anembodiment the second dielectric material 211 may be placed andplanarized as described above with respect to FIGS. 2E and 2F. Forexample, the second dielectric material 211 may be deposited and cured,and then a CMP, mechanical grinding, or chemical approach process may beutilized to planarize the second dielectric material 211 and expose thesecond vias 209. However, any suitable process may be utilized.

FIG. 12G illustrates the embodiment in which the first metallizationlayer 205 and the second vias 209 are formed using a damascene processto be partially landed. In this embodiment, instead of the second seedlayer 201 being formed first, the second dielectric material 211 isinitially deposited directly onto the first dielectric material 137 andthe first vias 135. For example, the second dielectric material 211 maybe formed as a polyimide derivative, and using, e.g., a spin-coatingprocess. However, any suitable material and method of deposition may beutilized.

Once the second dielectric material 211 is placed, the second dielectricmaterial 211 may be patterned in order to form the desired shape for thefirst metallization layer 205. In an embodiment the second dielectricmaterial 211 may be patterned by initially applying and then exposingand developing a photoresist in order to form a pattern in the shapedesired for first metallization layer 205.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second dielectricmaterial 211. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second dielectric material 211 andexposes the underlying first vias 135. However, any suitable process maybe used to transfer the pattern.

After the first vias 135 have been exposed, the openings through thesecond dielectric material 211 are then filled with a conductivematerial. In an embodiment a seed layer may be deposited along with oneor more barrier layers. In an embodiment the seed layer may be similarto the first seed layer 133, such as by being a titanium layer and acopper layer over the titanium layer that have been deposited using,e.g., physical vapor deposition to line the bottom and sidewall surfacesof the openings. However, any suitable materials and deposition processmay be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second dielectric material 211. However, anysuitable material and process may be utilized in order to fill theopenings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond dielectric material 211 are removed to form the firstmetallization layer 205. In an embodiment the excess portions may beremoved using, e.g., a planarizing process such as a chemical mechanicalpolishing process, a grinding process, other chemical processes,combinations of these, or the like. However, any suitable process ofembedding the conductive material into the second dielectric material211 and forming the first metallization layer 205 may be utilized.

FIG. 12G additionally illustrates that, once the first metallizationlayer 205 is formed, the second vias 209 may also be formed utilizing adamascene process. For example, once the first metallization layer 205is formed, the second via dielectric layer 213 may be deposited over thefirst metallization layer 205. In an embodiment the second viadielectric layer 213 may be a similar material and deposited using asimilar process as the second dielectric material 211, such as by beingformed as a polyimide derivative, and using e.g., a spin-coatingprocess. However, any suitable material and method of deposition may beutilized.

Once the second via dielectric layer 213 is placed, the second viadielectric layer 213 may be patterned in order to form the desired shapefor the second vias 209. In an embodiment the second via dielectriclayer 213 may be patterned by initially applying and then exposing anddeveloping a photoresist in order to form a pattern in the shape desiredfor second vias 209.

Once the pattern is defined into the photoresist, the pattern of thephotoresist may be transferred to the underlying second via dielectriclayer 213. In an embodiment the pattern may be transferred utilizing,e.g., an anisotropic etching process such as a reactive ion etch whichremoves exposed material of the second via dielectric layer 213 andexposes the underlying first metallization layer 205. However, anysuitable process may be used to transfer the pattern.

Additionally in this embodiment, the anisotropic etching process is notstopped when the top surface of the underlying first metallization layer205 is exposed. Rather, the etching process is continued so that aportion, but not all, of the second dielectric material 211 is removedto expose part of a sidewall of the first metallization layer 205.

After the first metallization layer 205 is exposed, the openings throughthe second via dielectric layer 213 and into the second dielectricmaterial 211 are then filled with a conductive material. In anembodiment a seed layer may be deposited along with one or more barrierlayers. In an embodiment the seed layer may be similar to the first seedlayer 133, such as by being a titanium layer and a copper layer over thetitanium layer that have been deposited using, e.g., physical vapordeposition to line the bottom and sidewall surfaces of the openings.However, any suitable materials and deposition process may be utilized.

Once the seed layer is formed, conductive material may be deposited tofill and overfill the openings. In an embodiment the conductive materialmay be copper that is deposited using a electroplating or electrolessplating process that utilizes the seed layer, and the process may becontinued until the conductive material fills and/or overfills theopenings within the second via dielectric layer 213 and the seconddielectric material 211. However, any suitable material and process maybe utilized in order to fill the openings with the conductive material.

After the openings have been filled, any excess portions of theconductive material that are located outside of the openings through thesecond via dielectric layer 213 and the second dielectric material 211are removed to form the second vias 209. In an embodiment the excessportions may be removed using, e.g., a planarizing process such as achemical mechanical polishing process, a grinding process, otherchemical processes, combinations of these, or the like. However, anysuitable process of embedding the conductive material into the secondvia dielectric layer 213 and the second dielectric material 211 andforming the second vias 209 may be utilized.

FIG. 13 illustrates that, once the first metallization layer 205 and thesecond vias 209 have been formed in this embodiment, similar processesmay be repeated in order to form the second metallization layer 307 andthe third via 309 (both formed using a single seed layer) and the thirdmetallization layer 311, all with the vias being partially landed on theunderlying metallization layer. Further, once the third metallizationlayer 311 is formed the passivation layer 301 may be formed andpatterned, the underbump metallizations 303 may be formed, and the thirdexternal connectors 305 may be placed as described above with respect toFIG. 3. However, any suitable methods and materials may be utilized.

FIG. 14 illustrates another embodiment in which the second vias 209 (orany suitable via) are formed as being partially landed on the firstmetallization layer 205. In this embodiment, however, the TIVs 401 areadditionally formed in order to electrically connect the first vias 135to an opposite side of the encapsulant 129. In an embodiment the TIVs401 may be formed as described above with respect to FIG. 4. Forexample, the TIVs may be formed using an electroplating process beforethe first semiconductor device 105 and the second semiconductor device107 are placed on the polymer layer 103. However, any suitable method offorming the TIVs 401 are fully intended to be included within the scopeof the embodiments.

FIG. 15 illustrates an embodiment in which, in addition to the TIVs 401as described in FIG. 14, the third passivation layer 403 is also formedbetween the first passivation layer 113 and the first externalconnectors 115. In this embodiment the third passivation layer 403 maybe formed as described above with respect to FIG. 4. However, anysuitable method and materials may be utilized.

FIG. 16 illustrates an embodiment in which the third passivation layer403 is utilized without the presence of the TIVs 401. In this embodimentsome of the first vias 135, instead of being electrically connected tothe TIVs 401, are instead utilized as dummy materials to providestructural support.

By forming the metallization layers and vias as described herein, a lowcost, high resolution metallization layer may be formed in order toredistribute the signals from the first semiconductor device 105 and thesecond semiconductor device 107. In particular, by utilizing the highresolution of photoresist and the same barrier/PVD seed layer during theformation of both the metallization layer and an associated via (therebyskipping the separate seed layer sputtering), a highly planarizedsurface with a fine pitch may be obtained, there is no PM layerresolution window issue, and a vertical profile may be obtained for thevias, thereby reducing the process windows and allowing more vias to beintegrated into a smaller area. Additionally, further cost savings canbe obtained by avoiding a seed layer etch for the formation of the vias(as the same seed layer is used for both the via and the metallizationlayer).

Once the processes described herein are completed, further processingmay be performed. For example, the first carrier substrate 101 may beremoved and, if the TIVs 401 are present, electrical connections such asexternal connections or external connections along with one or moreredistribution layers, may be formed. Once the external connections areformed, the entire package may be connected to another substrate, suchas a printed circuit board or interposer in preparation for usage.

In an embodiment a method of manufacturing a semiconductor deviceincludes forming a first via to a first semiconductor deviceencapsulated in an encapsulant; forming a seed layer over the first via;forming a metallization layer over the seed layer, the metallizationlayer having a first width; and forming a second via over themetallization layer, the second via having a second width less than thefirst width, wherein the forming the metallization layer and the formingthe second via both utilize the seed layer. In an embodiment, the methodfurther includes forming a third via; placing the first semiconductordevice next to the third via; and encapsulating the third via and thefirst semiconductor device to form the first semiconductor deviceencapsulated in the encapsulant. In an embodiment, the forming thesecond via forms a fully landed via. In an embodiment, the forming thesecond via forms a partially landed via. In an embodiment, the formingthe second via forms the second via to cover a sidewall of themetallization layer. In an embodiment, the forming the second via formsthe second via to partially cover a sidewall of the metallization layer.

In another embodiment a method of manufacturing a semiconductor deviceincludes depositing a seed layer over a first via, the first via beingelectrically connected to a first external connection of a first die,the first die being encapsulated within an encapsulant; patterning afirst opening into a first photoresist over the seed layer;electroplating a first metallization layer within the first opening ofthe first photoresist utilizing the seed layer; removing the firstphotoresist; after the removing the first photoresist, patterning asecond opening into a second photoresist over the first metallizationlayer; and electroplating a second via within the second opening of thesecond photoresist utilizing the seed layer. In an embodiment, thesecond opening exposes a top surface of the first metallization layer.In an embodiment, the second opening exposes a sidewall of the firstmetallization layer. In an embodiment, the second opening exposes aportion of the seed layer. In an embodiment, the method further includesremoving the second photoresist; depositing a dielectric material overthe first metallization layer; and planarizing the dielectric materialwith the second via. In an embodiment, the method further includes priorto the depositing the seed layer, forming a third via over a substrate;attaching the first die to the substrate after the forming the third viaover the substrate; and encapsulating the first die and the third viawith the encapsulant after the attaching the first die to the substrate.In an embodiment, the method further includes forming the first viaafter the encapsulating the first die. In an embodiment, the first diecomprises a first dielectric material and a second dielectric materialdifferent from the first dielectric material, wherein both the firstdielectric material and the second dielectric material are locatedbetween a contact pad and the first external connection.

In yet another embodiment a semiconductor device includes asemiconductor die encapsulated within an encapsulant; a first viaextending through a first dielectric layer to make contact with thesemiconductor die, the first via having almost straight sidewalls from atop of the first via to a bottom of the first via; a first seed layer inelectrical connection with the first via; a first metallization layerover and in physical contact with the first seed layer, the firstmetallization layer comprising a first material throughout the firstmetallization layer; a second via in direct physical contact with thefirst metallization layer, the second via comprising a second materialthroughout the second via; and a dielectric material covering sidewallsof both the first metallization layer and the second via, the dielectricmaterial comprising a third material throughout the dielectric material,wherein a first surface of the second via facing away from the firstmetallization layer is exposed by the dielectric material. In anembodiment, a portion of the dielectric material extends between thesecond via and the first dielectric layer. In an embodiment, the secondvia is in physical contact with the first seed layer. In an embodiment,the second via is fully landed on the first metallization layer. In anembodiment, the semiconductor device further includes a third viaextending from a first side of the encapsulant to a second side of theencapsulant. In an embodiment, the semiconductor device further includesa third via located in the first dielectric layer, the third via beingin physical contact with the encapsulant.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

What is claimed is:
 1. A method of manufacturing a semiconductor device,the method comprising: forming a first via to a first semiconductordevice encapsulated in an encapsulant; forming a seed layer over thefirst via; forming a metallization layer over the seed layer, themetallization layer having a first width; and forming a second via overthe metallization layer, the second via having a second width less thanthe first width, wherein the forming the metallization layer and theforming the second via both utilize the seed layer, and wherein theforming the second via forms the second via to cover a sidewall of themetallization layer, the sidewall being at a right angle to a surface ofthe metallization layer facing away from the first semiconductor device,wherein the seed layer is exposed during the forming the second via. 2.The method of claim 1, further comprising: forming a third via; placingthe first semiconductor device next to the third via; and encapsulatingthe third via and the first semiconductor device to form the firstsemiconductor device encapsulated in the encapsulant.
 3. The method ofclaim 1, wherein the encapsulant surrounds a through integrated fan outvia.
 4. The method of claim 1, further comprising: depositing adielectric material over the second via; and planarizing the dielectricmaterial to expose the second via.
 5. The method of claim 1, wherein thesecond via extends over the metallization layer a distance of between0.1 μm and 20 μM.
 6. The method of claim 1, wherein the second via has awidth adjacent to the metallization layer of between 0.1 μm and 20 μM.7. The method of claim 1, further comprising etching the seed layerusing the metallization layer and the second via as masks.
 8. A methodof manufacturing a semiconductor device, the method comprising:depositing a seed layer over a first via over a substrate, the first viabeing electrically connected to a first external connection of a firstdie, the first die being encapsulated within an encapsulant; patterninga first opening into a first photoresist over the seed layer;electroplating a first metallization layer within the first opening ofthe first photoresist utilizing the seed layer; removing the firstphotoresist; after the removing the first photoresist, patterning asecond opening into a second photoresist over the first metallizationlayer, wherein the second opening exposes a portion of the seed layer;and electroplating a second via within the second opening of the secondphotoresist utilizing the seed layer.
 9. The method of claim 8, whereinthe second opening exposes a top surface of the first metallizationlayer.
 10. The method of claim 8, further comprising: removing thesecond photoresist; depositing a dielectric material over the firstmetallization layer; and planarizing the dielectric material with thesecond via.
 11. The method of claim 8, further comprising: prior to thedepositing the seed layer, forming a third via over the substrate;attaching the first die to the substrate after the forming the third viaover the substrate; and encapsulating the first die and the third viawith the encapsulant after the attaching the first die to the substrate.12. The method of claim 11, further comprising forming the first viaafter the encapsulating the first die.
 13. The method of claim 8,wherein the first die comprises a first dielectric material and a seconddielectric material different from the first dielectric material,wherein both the first dielectric material and the second dielectricmaterial are located between a contact pad and the first externalconnection.
 14. The method of claim 8, wherein the encapsulant surroundsa through integrated fan out via.
 15. The method of claim 8, wherein thesecond via extends over the first metallization layer a distance ofbetween 0.1 μm and 20 μM.
 16. A method of manufacturing a semiconductordevice, the method comprising: encapsulating a semiconductor die withinan encapsulant; forming a first via extending through a first dielectriclayer to electrically couple to the semiconductor die, the first viahaving straight sidewalls from a top of the first via to a bottom of thefirst via; forming a first seed layer in electrical connection with thefirst via; forming a first metallization layer over and in physicalcontact with the first seed layer, the first metallization layercomprising a first material throughout the first metallization layer;forming a second via in direct physical contact with the firstmetallization layer, the second via comprising a second materialthroughout the second via, wherein the second via is in physical contactwith the first seed layer; and forming a dielectric material coveringsidewalls of both the first metallization layer and the second via, thedielectric material comprising a third material throughout thedielectric material, wherein a first surface of the second via facingaway from the first metallization layer is exposed by the dielectricmaterial.
 17. The method of claim 16, wherein a portion of thedielectric material extends between the second via and the firstdielectric layer.
 18. The method of claim 16, wherein the second via isfully landed on the first metallization layer.
 19. The method of claim16, further comprising forming a third via, wherein after the formingthe third via the third via extends from a first side of the encapsulantto a second side of the encapsulant.
 20. The method of claim 16, furthercomprising forming a third via located in the first dielectric layer,the third via being in physical contact with the encapsulant.